But given that the huge majority of drive failures are caused by head crashes or failures of the electronics, it isn't anything I'd worry about.

Honestly, I never know why a given drive fails when it does. All I ever know is that I start gettting errors and I replace the thing. For all I know, every failure I've had could have been spindle bearings.

Or gnomes.

I'm starting to wonder about gnomes possibly being the culprit in many things. Sometimes I think I catch a glimpse of one out of the corner of my eye, but it scurries out of sight before I can make a positive identification.